Improvement in steam-engine pistons



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RICHARD WITTY, OF

CHICAGO, ILLINOIS.

Letters Patent No. 94,371, dated August 3l, 1869,

IMPROVEMENT IN STEAM-ENGIN PISTONS.

The chedule referred to in these Letters Patent and making part of thesame.

To all whom it may conce/rn Be it known that I, RICHARD Wlrrr, ofChicago,

in the 4county of Cook, and in the State of Illinois,

have invented certain new and useful Improvements in Pistons forSteam-Engines; and do hereby declare `that the following is a full,clear, and exact descrip;

tion thereof', reference being had to the accompanying drawings, and tothe letters of reference marked thereoi, making a part of thisspecification.

resent a vertical section of a piston-head, with valves attached.

A represents the piston and B the follower, placed asnitable distanceapart, and through the centre of which the piston-rod passes, the spacebetween the piston and follower to be closed at the outer circumferenceby a metal ring.

In the piston A are placed mire-seats a a, and in the follower B are acorresponding number of valveseats a a.

Spindles b b are then passed through the same, which are at each endprovided with a valve, d, said valves being held on the spindle by jamnuts e e, and on each end of the spindle is placed a spiral spring, t',

which extends beyond the spindle, asseen in the ber desired, aresoplaced in the piston and followerl that when the valves on either sideare closed, said valves shall be flush, or even with the surface of thepiston, or follower, and the spindles b b are of such length, that atthe proper time both valves on each spindle will be open, allowing freepassage of the steam through the piston. Y l

The valves will -be closed at the commencement of the stroke by thepressu'reof steam from thl boiler,

and are opened by coming against the cylinder-head a little before` thestroke is completed, and then both valves will belopen, allowing asteam-passage through the piston.

The springs t' i, on the ends of the spindles, of course relieve theconcussion or shock against thecylinder-head.

The steam that is to be reworked will, when both Valves are opened, asabove mentioned, then pass through the piston, and as soon as the pistoncommences to return, the valves on the other side are 'closed in likemanner, the exhaustible steam -in the position expanding the ring orrings that surround the piston.

Having thus fully described my invention, What I claim as new, anddesire to secure by Letters PatentLis- Y The construction andarrangement of the valveseats a ai', spindles b b, valves d d, nuts c e,and springs i t', with reference to the pist-on A and follower B, allsubstantially as shown and described,

In testimony that I claim the foregoing, I have hereunto set my hand andseal, this 29th day of May, 1869.

RICHARD TITTX [1.. s.] Witnesses:

E. WASHBURN, Jr., Win'. HARRIS DAY.

